Techniques and apparatuses for waveform signaling for downlink communications

ABSTRACT

When a base station is capable of using multiple different types of waveforms for a downlink communication to a UE, the UE may waste processing resources attempting to receive and/or process the downlink communication. For example, the UE may cycle through various possible types of waveforms in an attempt to process the downlink communication. Techniques described herein use waveform signaling for downlink communications to notify the UE of a type of waveform being used for a downlink communication, thereby conserving UE resources (e.g., processing resources, memory resources, RF resources, and/or the like) that would otherwise be wasted attempting to process the downlink communication using multiple types of waveforms.

CROSS-REFERENCE TO RELATED APPLICATIONS UNDER 35 U.S.C. § 119

This application is a divisional of U.S. patent application Ser. No.15/726,229, filed Oct. 5, 2017, entitled “TECHNIQUES AND APPARATUSES FORWAVEFORM SIGNALING FOR DOWNLINK COMMUNICATIONS,” which claims priorityto U.S. Provisional Patent Application No. 62/475,512, filed Mar. 23,2017, entitled “TECHNIQUES AND APPARATUSES FOR WAVEFORM SIGNALING FORDOWNLINK COMMUNICATIONS,” which are hereby expressly incorporated byreference herein.

BACKGROUND Field

Aspects of the present disclosure generally relate to wirelesscommunication, and more particularly to techniques and apparatuses forwaveform signaling for downlink communications.

Background

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, and/or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations(BSs) that can support communication for a number of user equipment(UEs). A UE may communicate with a BS via the downlink and uplink. Thedownlink (or forward link) refers to the communication link from the BSto the UE, and the uplink (or reverse link) refers to the communicationlink from the UE to the BS. As will be described in more detail herein,a BS may be referred to as a Node B, a gNB, an access point (AP), aradio head, a transmit receive point (TRP), a 5G BS, a 5G Node B, and/orthe like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless communication devices to communicate on a municipal,national, regional, and even global level. 5G, which may also bereferred to as New Radio (NR), is a set of enhancements to the LTEmobile standard promulgated by the Third Generation Partnership Project(3GPP). 5G is designed to better support mobile broadband Internetaccess by improving spectral efficiency, lowering costs, improvingservices, making use of new spectrum, and better integrating with otheropen standards using OFDM with a cyclic prefix (CP) (CP-OFDM) on thedownlink (DL), using CP-OFDM and/or SC-1-DM (e.g., also known asdiscrete Fourier transform spread ODFM (DFT-s-OFDM)) on the uplink (UL),as well as supporting beamforming, multiple-input multiple-output (MIMO)antenna technology, and carrier aggregation. However, as the demand formobile broadband access continues to increase, there exists a need forfurther improvements in LTE and 5G technologies. Preferably, theseimprovements should be applicable to other multiple access technologiesand the telecommunication standards that employ these technologies.

In 5G, different types of waveforms may be used for uplink and/ordownlink communications. For example, such communications may betransmitted and/or received using a DFT-s-OFDM waveform, a CP-OFDMwaveform, and/or the like, depending on one or more factors, such as anetwork condition, a performance parameter, a type of communicationbeing transmitted, and/or the like. For example, a DFT-s-OFDM waveformmay be used to achieve performance benefits associated with a lower peakto average power ratio (PAPR), a CP-OFDM waveform may be used to achieveperformance benefits associated with a higher spectral efficiency,and/or the like. When a base station is capable of using multipledifferent types of waveforms for a downlink communication to a UE, theUE may waste processing resources attempting to receive and/or processthe downlink communication. For example, the UE may cycle throughvarious possible types of waveforms in an attempt to process thedownlink communication.

SUMMARY

Techniques described herein use waveform signaling for downlinkcommunications to notify the UE of a type of waveform being used for adownlink communication, thereby conserving UE resources (e.g.,processing resources, memory resources, RF resources, and/or the like)that would otherwise be wasted attempting to process the downlinkcommunication using multiple types of waveforms.

In an aspect of the disclosure, a method, a user equipment (UE), a basestation, an apparatus, and a computer program product are provided.

In some aspects, the method may include receiving, by a UE, a waveformindication in a first downlink channel that uses a first waveform of aplurality of waveforms; determining, by the UE, a second waveform, ofthe plurality of waveforms, to be used for one or more downlinkcommunications in a second downlink channel based at least in part onthe waveform indication received in the first downlink channel; andprocessing, by the UE, the one or more downlink communications receivedin the second downlink channel using the second waveform.

In some aspects, the method may include generating, by a base station, afirst transmission layer of a multi-layer communication using a firstwaveform of a plurality of waveforms; generating, by the base station, asecond transmission layer of the multi-layer communication using asecond waveform of the plurality of waveforms, wherein the firstwaveform and the second waveform are different; and transmitting, by thebase station, the first transmission layer and the second transmissionlayer using a same time resource and a same frequency resource, whereinthe first transmission layer is transmitted using the first waveform andthe second transmission layer is transmitted using the second waveform.

In some aspects, the method may include receiving, by a first UE, afirst indication of a first waveform, of a plurality of waveforms, to beused for one or more downlink communications associated with the firstUE; receiving, by the first UE, a second indication of a secondwaveform, of the plurality of waveforms, associated with downlinkcommunications of a second UE; receiving, by the first UE, the one ormore downlink communications using the first waveform; and processing,by the first UE, the one or more downlink communications based at leastin part on the second indication of the second waveform.

In some aspects, the UE may include a memory and one or more processorscoupled to the memory. The memory and the one or more processors may beconfigured to receive a waveform indication in a first downlink channelthat uses a first waveform of a plurality of waveforms; determine asecond waveform, of the plurality of waveforms, to be used for one ormore downlink communications in a second downlink channel based at leastin part on the waveform indication received in the first downlinkchannel; and process the one or more downlink communications received inthe second downlink channel using the second waveform.

In some aspects, the base station may include a memory and one or moreprocessors coupled to the memory. The memory and the one or moreprocessors may be configured to generate a first transmission layer of amulti-layer communication using a first waveform of a plurality ofwaveforms; generate a second transmission layer of the multi-layercommunication using a second waveform of the plurality of waveforms,wherein the first waveform and the second waveform are different; andtransmit the first transmission layer and the second transmission layerusing a same time resource and a same frequency resource, wherein thefirst transmission layer is transmitted using the first waveform and thesecond transmission layer is transmitted using the second waveform.

In some aspects, a first UE may include a memory and one or moreprocessors coupled to the memory. The memory and the one or moreprocessors may be configured to receive a first indication of a firstwaveform, of a plurality of waveforms, to be used for one or moredownlink communications associated with the first UE; receive a secondindication of a second waveform, of the plurality of waveforms,associated with downlink communications of a second UE; receive the oneor more downlink communications using the first waveform; and processthe one or more downlink communications based at least in part on thesecond indication of the second waveform.

In some aspects, the apparatus may include means for receiving awaveform indication in a first downlink channel that uses a firstwaveform of a plurality of waveforms; means for determining a secondwaveform, of the plurality of waveforms, to be used for one or moredownlink communications in a second downlink channel based at least inpart on the waveform indication received in the first downlink channel;and means for processing the one or more downlink communicationsreceived in the second downlink channel using the second waveform.

In some aspects, the apparatus may include means for generating a firsttransmission layer of a multi-layer communication using a first waveformof a plurality of waveforms; means for generating a second transmissionlayer of the multi-layer communication using a second waveform of theplurality of waveforms, wherein the first waveform and the secondwaveform are different; and means for transmitting the firsttransmission layer and the second transmission layer using a same timeresource and a same frequency resource, wherein the first transmissionlayer is transmitted using the first waveform and the secondtransmission layer is transmitted using the second waveform.

In some aspects, the apparatus may include means for receiving a firstindication of a first waveform, of a plurality of waveforms, to be usedfor one or more downlink communications associated with a first UE;means for receiving a second indication of a second waveform, of theplurality of waveforms, associated with downlink communications of asecond UE; means for receiving the one or more downlink communicationsusing the first waveform; and means for processing the one or moredownlink communications based at least in part on the second indicationof the second waveform.

In some aspects, the computer program product may include anon-transitory computer-readable medium storing one or more instructionsfor wireless communication. The one or more instructions, when executedby one or more processors, may cause the one or more processors toreceive a waveform indication in a first downlink channel that uses afirst waveform of a plurality of waveforms; determine a second waveform,of the plurality of waveforms, to be used for one or more downlinkcommunications in a second downlink channel based at least in part onthe waveform indication received in the first downlink channel; andprocess the one or more downlink communications received in the seconddownlink channel using the second waveform.

In some aspects, the computer program product may include anon-transitory computer-readable medium storing one or more instructionsfor wireless communication. The one or more instructions, when executedby one or more processors, may cause the one or more processors togenerate a first transmission layer of a multi-layer communication usinga first waveform of a plurality of waveforms; generate a secondtransmission layer of the multi-layer communication using a secondwaveform of the plurality of waveforms, wherein the first waveform andthe second waveform are different; and transmit the first transmissionlayer and the second transmission layer using a same time resource and asame frequency resource, wherein the first transmission layer istransmitted using the first waveform and the second transmission layeris transmitted using the second waveform.

In some aspects, the computer program product may include anon-transitory computer-readable medium storing one or more instructionsfor wireless communication. The one or more instructions, when executedby one or more processors, may cause the one or more processors toreceive a first indication of a first waveform, of a plurality ofwaveforms, to be used for one or more downlink communications associatedwith a first UE; receive a second indication of a second waveform, ofthe plurality of waveforms, associated with downlink communications of asecond UE; receive the one or more downlink communications using thefirst waveform; and process the one or more downlink communicationsbased at least in part on the second indication of the second waveform.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and processing system assubstantially described herein with reference to and as illustrated bythe accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description, and not as a definition of the limits ofthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is diagram illustrating an example of a wireless communicationnetwork.

FIG. 2 is a diagram illustrating an example of a base station incommunication with a user equipment (UE) in a wireless communicationnetwork.

FIG. 3 is a diagram illustrating an example of a frame structure in awireless communication network.

FIG. 4 is a diagram illustrating two example subframe formats with thenormal cyclic prefix.

FIG. 5 is a diagram illustrating an example logical architecture of adistributed radio access network (RAN).

FIG. 6 is a diagram illustrating an example physical architecture of adistributed RAN.

FIG. 7 is a diagram illustrating an example of a downlink (DL)-centricwireless communication structure.

FIG. 8 is a diagram illustrating an example of an uplink (UL)-centricwireless communication structure.

FIG. 9 is a diagram illustrating an example of waveform signaling fordownlink communications.

FIG. 10 is a diagram illustrating another example of waveform signalingfor downlink communications.

FIG. 11 is a flow chart of a method of wireless communication.

FIG. 12 is a flow chart of another method of wireless communication.

FIG. 13 is a flow chart of another method of wireless communication.

FIG. 14 is a conceptual data flow diagram illustrating the data flowbetween different modules/means/components in an example apparatus.

FIG. 15 is a diagram illustrating an example of a hardwareimplementation for an apparatus employing a processing system.

FIG. 16 is a conceptual data flow diagram illustrating the data flowbetween different modules/means/components in another example apparatus.

FIG. 17 is a diagram illustrating another example of a hardwareimplementation for an apparatus employing a processing system.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of various configurations and isnot intended to represent the configurations in which the conceptsdescribed herein may be practiced. The detailed description includesspecific details for the purposes of providing a thorough understandingof various concepts. However, it will be apparent to those skilled inthe art that these concepts may be practiced without these specificdetails. In some instances, well-known structures and components areshown in block diagram form in order to avoid obscuring such concepts.

Several aspects of telecommunication systems will now be presented withreference to various apparatus and methods. These apparatus and methodswill be described in the following detailed description and illustratedin the accompanying drawings by various blocks, modules, components,circuits, steps, processes, algorithms, and/or the like (collectivelyreferred to as “elements”). These elements may be implemented usingelectronic hardware, computer software, or any combination thereof.Whether such elements are implemented as hardware or software dependsupon the particular application and design constraints imposed on theoverall system.

By way of example, an element, or any portion of an element, or anycombination of elements may be implemented with a “processing system”that includes one or more processors. Examples of processors includemicroprocessors, microcontrollers, digital signal processors (DSPs),field programmable gate arrays (FPGAs), programmable logic devices(PLDs), state machines, gated logic, discrete hardware circuits, andother suitable hardware configured to perform the various functionalitydescribed throughout this disclosure. One or more processors in theprocessing system may execute software. Software shall be construedbroadly to mean instructions, instruction sets, code, code segments,program code, programs, subprograms, software modules, applications,software applications, software packages, routines, subroutines,objects, executables, threads of execution, procedures, functions,and/or the like, whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, the functions describedmay be implemented in hardware, software, firmware, or any combinationthereof. If implemented in software, the functions may be stored on orencoded as one or more instructions or code on a computer-readablemedium. Computer-readable media includes computer storage media. Storagemedia may be any available media that can be accessed by a computer. Byway of example, and not limitation, such computer-readable media cancomprise a random-access memory (RAM), a read-only memory (ROM), anelectrically erasable programmable ROM (EEPROM), compact disk ROM(CD-ROM) or other optical disk storage, magnetic disk storage or othermagnetic storage devices, combinations of the aforementioned types ofcomputer-readable media, or any other medium that can be used to storecomputer executable code in the form of instructions or data structuresthat can be accessed by a computer.

An access point (“AP”) may comprise, be implemented as, or known as aNodeB, a Radio Network Controller (“RNC”), an eNodeB (eNB), a BaseStation Controller (“BSC”), a Base Transceiver Station (“BTS”), a BaseStation (“BS”), a Transceiver Function (“TF”), a Radio Router, a RadioTransceiver, a Basic Service Set (“BSS”), an Extended Service Set(“ESS”), a Radio Base Station (“RBS”), a Node B (NB), a gNB, a 5G NB, a5G BS, a Transmit Receive Point (TRP), or some other terminology.

An access terminal (“AT”) may comprise, be implemented as, or be knownas an access terminal, a subscriber station, a subscriber unit, a mobilestation, a remote station, a remote terminal, a user terminal, a useragent, a user device, user equipment (UE), a user station, a wirelessnode, or some other terminology. In some aspects, an access terminal maycomprise a cellular telephone, a smart phone, a cordless telephone, aSession Initiation Protocol (“SIP”) phone, a wireless local loop (“WLL”)station, a personal digital assistant (“PDA”), a tablet, a netbook, asmartbook, an ultrabook, a handheld device having wireless connectioncapability, a Station (“STA”), or some other suitable processing deviceconnected to a wireless modem. Accordingly, one or more aspects taughtherein may be incorporated into a phone (e.g., a cellular phone, a smartphone), a computer (e.g., a desktop), a portable communication device, aportable computing device (e.g., a laptop, a personal data assistant, atablet, a netbook, a smartbook, an ultrabook), wearable device (e.g.,smart watch, smart glasses, smart bracelet, smart wristband, smart ring,smart clothing, and/or the like), medical devices or equipment,biometric sensors/devices, an entertainment device (e.g., music device,video device, satellite radio, gaming device, and/or the like), avehicular component or sensor, smart meters/sensors, industrialmanufacturing equipment, a global positioning system device, or anyother suitable device that is configured to communicate via a wirelessor wired medium. In some aspects, the node is a wireless node. Awireless node may provide, for example, connectivity for or to a network(e.g., a wide area network such as the Internet or a cellular network)via a wired or wireless communication link.

Some UEs may be considered machine-type communication (MTC) UEs, whichmay include remote devices that may communicate with a base station,another remote device, or some other entity. Machine type communications(MTC) may refer to communication involving at least one remote device onat least one end of the communication and may include forms of datacommunication which involve one or more entities that do not necessarilyneed human interaction. MTC UEs may include UEs that are capable of MTCcommunications with MTC servers and/or other MTC devices through PublicLand Mobile Networks (PLMN), for example. Examples of MTC devicesinclude sensors, meters, location tags, monitors, drones, robots/roboticdevices, and/or the like. In some aspects, MTC devices may be referredto as enhanced MTC (eMTC) devices, LTE category M1 (LTE-M) devices,machine to machine (M2M) devices, and/or the like. Additionally, oralternatively, some UEs may be narrowband Internet of things (NB-IoT)devices.

It is noted that while aspects may be described herein using terminologycommonly associated with 3G and/or 4G wireless technologies, aspects ofthe present disclosure can be applied in other generation-basedcommunication systems, such as 5G and later.

FIG. 1 is a diagram illustrating a network 100 in which aspects of thepresent disclosure may be practiced. The network 100 may be an LTEnetwork or some other wireless network, such as a 5G network. Wirelessnetwork 100 may include a number of BSs 110 (shown as BS 110 a, BS 110b, BS 110 c, and BS 110 d) and other network entities. ABS is an entitythat communicates with user equipment (UEs) and may also be referred toas a base station, a 5G BS, a Node B, a gNB, a 5G NB, an access point, aTRP, and/or the like. Each BS may provide communication coverage for aparticular geographic area. In 3GPP, the term “cell” can refer to acoverage area of a BS and/or a BS subsystem serving this coverage area,depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1, a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “5G BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some examples, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some examples, the BSs may be interconnected to oneanother and/or to one or more other BSs or network nodes (not shown) inthe access network 100 through various types of backhaul interfaces suchas a direct physical connection, a virtual network, and/or the likeusing any suitable transport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1, a relay station 110 d may communicate with macro BS 110 a and aUE 120 d in order to facilitate communication between BS 110 a and UE120 d. A relay station may also be referred to as a relay BS, a relaybase station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/orthe like. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impact on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 Watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, e.g., directly or indirectly via a wireless orwireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, and/or the like. A UE may be a cellularphone (e.g., a smart phone), a personal digital assistant (PDA), awireless modem, a wireless communication device, a handheld device, alaptop computer, a cordless phone, a wireless local loop (WLL) station,a tablet, a camera, a gaming device, a netbook, a smartbook, anultrabook, medical device or equipment, biometric sensors/devices,wearable devices (smart watches, smart clothing, smart glasses, smartwrist bands, smart jewelry (e.g., smart ring, smart bracelet)), anentertainment device (e.g., a music or video device, or a satelliteradio), a vehicular component or sensor, smart meters/sensors,industrial manufacturing equipment, a global positioning system device,or any other suitable device that is configured to communicate via awireless or wired medium. Some UEs may be considered evolved or enhancedmachine-type communication (eMTC) UEs. MTC and eMTC UEs include, forexample, robots, drones, remote devices, such as sensors, meters,monitors, location tags, and/or the like, that may communicate with abase station, another device (e.g., remote device), or some otherentity. A wireless node may provide, for example, connectivity for or toa network (e.g., a wide area network such as Internet or a cellularnetwork) via a wired or wireless communication link. Some UEs may beconsidered Internet-of-Things (IoT) devices. Some UEs may be considereda Customer Premises Equipment (CPE).

When a BS 110 is capable of using multiple different types of waveformsfor a downlink communication to a UE 120, the UE 120 may wasteprocessing resources attempting to receive and/or process the downlinkcommunication. For example, the UE 120 may cycle through variouspossible types of waveforms in an attempt to process the downlinkcommunication. Techniques described herein use waveform signaling fordownlink communications to notify the UE 120 of a type of waveform beingused for a downlink communication, thereby conserving UE resources(e.g., processing resources, memory resources, RF resources, and/or thelike) that would otherwise be wasted attempting to process the downlinkcommunication using multiple types of waveforms.

In FIG. 1, a solid line with double arrows indicates desiredtransmissions between a UE and a serving BS, which is a BS designated toserve the UE on the downlink and/or uplink. A dashed line with doublearrows indicates potentially interfering transmissions between a UE anda BS.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology, an air interface, and/or the like. A frequency mayalso be referred to as a carrier, a frequency channel, and/or the like.Each frequency may support a single RAT in a given geographic area inorder to avoid interference between wireless networks of different RATs.In some cases, 5G RAT networks may be deployed.

In some examples, access to the air interface may be scheduled, whereina scheduling entity (e.g., a base station) allocates resources forcommunication among some or all devices and equipment within thescheduling entity's service area or cell. Within the present disclosure,as discussed further below, the scheduling entity may be responsible forscheduling, assigning, reconfiguring, and releasing resources for one ormore subordinate entities. That is, for scheduled communication,subordinate entities utilize resources allocated by the schedulingentity.

Base stations are not the only entities that may function as ascheduling entity. That is, in some examples, a UE may function as ascheduling entity, scheduling resources for one or more subordinateentities (e.g., one or more other UEs). In this example, the UE isfunctioning as a scheduling entity, and other UEs utilize resourcesscheduled by the UE for wireless communication. A UE may function as ascheduling entity in a peer-to-peer (P2P) network, and/or in a meshnetwork. In a mesh network example, UEs may optionally communicatedirectly with one another in addition to communicating with thescheduling entity.

Thus, in a wireless communication network with a scheduled access totime-frequency resources and having a cellular configuration, a P2Pconfiguration, and a mesh configuration, a scheduling entity and one ormore subordinate entities may communicate utilizing the scheduledresources.

As indicated above, FIG. 1 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 1.

FIG. 2 shows a block diagram 200 of a design of base station 110 and UE120, which may be one of the base stations and one of the UEs in FIG. 1.Base station 110 may be equipped with T antennas 234 a through 234 t,and UE 120 may be equipped with R antennas 252 a through 252 r, where ingeneral T>1 and R>1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation orcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI), and/or the like) and controlinformation (e.g., CQI requests, grants, upper layer signaling, and/orthe like) and provide overhead symbols and control symbols. Transmitprocessor 220 may also generate reference symbols for reference signals(e.g., the CRS) and synchronization signals (e.g., the primarysynchronization signal (PSS) and secondary synchronization signal(SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor230 may perform spatial processing (e.g., precoding) on the datasymbols, the control symbols, the overhead symbols, and/or the referencesymbols, if applicable, and may provide T output symbol streams to Tmodulators (MODs) 232 a through 232 t. Each modulator 232 may process arespective output symbol stream (e.g., for OFDM and/or the like) toobtain an output sample stream. Each modulator 232 may further process(e.g., convert to analog, amplify, filter, and upconvert) the outputsample stream to obtain a downlink signal. T downlink signals frommodulators 232 a through 232 t may be transmitted via T antennas 234 athrough 234 t, respectively. According to certain aspects described inmore detail below, the synchronization signals can be generated withlocation encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM and/or the like) to obtain received symbols. A MIMO detector 256may obtain received symbols from all R demodulators 254 a through 254 r,perform MIMO detection on the received symbols if applicable, andprovide detected symbols. A receive (RX) processor 258 may process(e.g., demodulate and decode) the detected symbols, provide decoded datafor UE 120 to a data sink 260, and provide decoded control informationand system information to a controller/processor 280. A channelprocessor may determine RSRP, RSSI, RSRQ, CQI, and/or the like.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to basestation 110. At base station 110, the uplink signals from UE 120 andother UEs may be received by antennas 234, processed by demodulators232, detected by a MIMO detector 236 if applicable, and furtherprocessed by a receive processor 238 to obtain decoded data and controlinformation sent by UE 120. Receive processor 238 may provide thedecoded data to a data sink 239 and the decoded control information tocontroller/processor 240. Base station 110 may include communicationunit 244 and communicate to network controller 130 via communicationunit 244. Network controller 130 may include communication unit 294,controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform waveformsignaling for downlink communications. For example, controller/processor240 of base station 110, controller/processor 280 of UE 120, and/or anyother component(s) of FIG. 2 may perform or direct operations of, forexample, method 1100 of FIG. 11, method 1200 of FIG. 12, method 1300 ofFIG. 13, and/or other processes as described herein. Memories 242 and282 may store data and program codes for BS 110 and UE 120,respectively. A scheduler 246 may schedule UEs for data transmission onthe downlink and/or uplink.

As indicated above, FIG. 2 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 2.

FIG. 3 shows an example frame structure 300 for FDD in atelecommunications system (e.g., LTE). The transmission timeline foreach of the downlink and uplink may be partitioned into units of radioframes. Each radio frame may have a predetermined duration (e.g., 10milliseconds (ms)) and may be partitioned into 10 subframes with indicesof 0 through 9. Each subframe may include two slots. Each radio framemay thus include 20 slots with indices of 0 through 19. Each slot mayinclude L symbol periods, e.g., seven symbol periods for a normal cyclicprefix (as shown in FIG. 3) or six symbol periods for an extended cyclicprefix. The 2L symbol periods in each subframe may be assigned indicesof 0 through 2L−1.

While some techniques are described herein in connection with frames,subframes, slots, and/or the like, these techniques may equally apply toother types of wireless communication structures, which may be referredto using terms other than “frame,” “subframe,” “slot,” and/or the likein 5G. In some aspects, a wireless communication structure may refer toa periodic time-bounded communication unit defined by a wirelesscommunication standard and/or protocol.

In certain telecommunications (e.g., LTE), a BS may transmit a primarysynchronization signal (PSS) and a secondary synchronization signal(SSS) on the downlink in the center of the system bandwidth for eachcell supported by the BS. The PSS and SSS may be transmitted in symbolperiods 6 and 5, respectively, in subframes 0 and 5 of each radio framewith the normal cyclic prefix, as shown in FIG. 3. The PSS and SSS maybe used by UEs for cell search and acquisition. The BS may transmit acell-specific reference signal (CRS) across the system bandwidth foreach cell supported by the BS. The CRS may be transmitted in certainsymbol periods of each subframe and may be used by the UEs to performchannel estimation, channel quality measurement, and/or other functions.The BS may also transmit a physical broadcast channel (PBCH) in symbolperiods 0 to 3 in slot 1 of certain radio frames. The PBCH may carrysome system information. The BS may transmit other system informationsuch as system information blocks (SIBs) on a physical downlink sharedchannel (PDSCH) in certain subframes. The BS may transmit controlinformation/data on a physical downlink control channel (PDCCH) in thefirst B symbol periods of a subframe, where B may be configurable foreach subframe. The BS may transmit traffic data and/or other data on thePDSCH in the remaining symbol periods of each subframe. In some aspects,one or more of these signals and/or channels may carry a waveformindication for another signal and/or channel, as described in moredetail elsewhere herein.

In other systems (e.g., such as 5G systems), a Node B may transmit theseor other signals in these locations or in different locations of thesubframe.

As indicated above, FIG. 3 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 3.

FIG. 4 shows two example subframe formats 410 and 420 with the normalcyclic prefix. The available time frequency resources may be partitionedinto resource blocks. Each resource block may cover 12 subcarriers inone slot and may include a number of resource elements. Each resourceelement may cover one subcarrier in one symbol period and may be used tosend one modulation symbol, which may be a real or complex value.

Subframe format 410 may be used for two antennas. A CRS may betransmitted from antennas 0 and 1 in symbol periods 0, 4, 7 and 11. Areference signal is a signal that is known a priori by a transmitter anda receiver and may also be referred to as pilot. A CRS is a referencesignal that is specific for a cell, e.g., generated based at least inpart on a cell identity (ID). In FIG. 4, for a given resource elementwith label Ra, a modulation symbol may be transmitted on that resourceelement from antenna a, and no modulation symbols may be transmitted onthat resource element from other antennas. Subframe format 420 may beused with four antennas. A CRS may be transmitted from antennas 0 and 1in symbol periods 0, 4, 7 and 11 and from antennas 2 and 3 in symbolperiods 1 and 8. For both subframe formats 410 and 420, a CRS may betransmitted on evenly spaced subcarriers, which may be determined basedat least in part on cell ID. CRSs may be transmitted on the same ordifferent subcarriers, depending on their cell IDs. For both subframeformats 410 and 420, resource elements not used for the CRS may be usedto transmit data (e.g., traffic data, control data, and/or other data).

The PSS, SSS, CRS and PBCH in LTE are described in 3GPP TS 36.211,entitled “Evolved Universal Terrestrial Radio Access (E-UTRA); PhysicalChannels and Modulation,” which is publicly available.

An interlace structure may be used for each of the downlink and uplinkfor FDD in certain telecommunications systems (e.g., LTE). For example,Q interlaces with indices of 0 through Q−1 may be defined, where Q maybe equal to 4, 6, 8, 10, or some other value. Each interlace may includesubframes that are spaced apart by Q frames. In particular, interlace qmay include subframes q, q+Q, q+2Q, and/or the like, where q ∈{0, . . ., Q−1}.

The wireless network may support hybrid automatic retransmission request(HARQ) for data transmission on the downlink and uplink. For HARQ, atransmitter (e.g., a BS) may send one or more transmissions of a packetuntil the packet is decoded correctly by a receiver (e.g., a UE) or someother termination condition is encountered. For synchronous HARQ, alltransmissions of the packet may be sent in subframes of a singleinterlace. For asynchronous HARQ, each transmission of the packet may besent in any subframe.

A UE may be located within the coverage of multiple BSs. One of theseBSs may be selected to serve the UE. The serving BS may be selectedbased at least in part on various criteria such as received signalstrength, received signal quality, path loss, and/or the like. Receivedsignal quality may be quantified by a signal-to-noise-and-interferenceratio (SINR), or a reference signal received quality (RSRQ), or someother metric. The UE may operate in a dominant interference scenario inwhich the UE may observe high interference from one or more interferingBSs.

While aspects of the examples described herein may be associated withLTE technologies, aspects of the present disclosure may be applicablewith other wireless communication systems, such as 5G technologies.

5G may refer to radios configured to operate according to a new airinterface (e.g., other than Orthogonal Frequency Divisional MultipleAccess (OFDMA)-based air interfaces) or fixed transport layer (e.g.,other than Internet Protocol (IP)). In aspects, 5G may utilize OFDM witha CP (herein referred to as cyclic prefix OFDM or CP-OFDM) and/orSC-1-DM on the uplink, may utilize CP-OFDM on the downlink and includesupport for half-duplex operation using TDD. In aspects, 5G may, forexample, utilize OFDM with a CP (herein referred to as CP-OFDM) and/ordiscrete Fourier transform spread orthogonal frequency-divisionmultiplexing (DFT-s-OFDM) on the uplink, may utilize CP-OFDM on thedownlink and include support for half-duplex operation using TDD. 5G mayinclude Enhanced Mobile Broadband (eMBB) service targeting widebandwidth (e.g., 80 megahertz (MHz) and beyond), millimeter wave (mmW)targeting high carrier frequency (e.g., 60 gigahertz (GHz)), massive MTC(mMTC) targeting non-backward compatible MTC techniques, and/or missioncritical targeting ultra reliable low latency communications (URLLC)service. In some aspects, DFT-s-OFDM, CP-OFDM, and/or the like may beused on the downlink, and a BS may signal a type of waveform to be usedfor downlink communication to a UE, as described in more detailelsewhere herein.

A single component carrier bandwidth of 100 MHZ may be supported. 5Gresource blocks may span 12 sub-carriers with a sub-carrier bandwidth of75 kilohertz (kHz) over a 0.1 ms duration. Each radio frame may include50 subframes with a length of 10 ms. Consequently, each subframe mayhave a length of 0.2 ms. Each subframe may indicate a link direction(e.g., DL or UL) for data transmission and the link direction for eachsubframe may be dynamically switched. Each subframe may include DL/ULdata as well as DL/UL control data. UL and DL subframes for 5G may be asdescribed in more detail below with respect to FIGS. 7 and 8.

Beamforming may be supported and beam direction may be dynamicallyconfigured. MIMO transmissions with precoding may also be supported.MIMO configurations in the DL may support up to 8 transmit antennas withmulti-layer DL transmissions up to 8 streams and up to 2 streams per UE.Multi-layer transmissions with up to 2 streams per UE may be supported.Aggregation of multiple cells may be supported with up to 8 servingcells. Alternatively, 5G may support a different air interface, otherthan an OFDM-based interface. 5G networks may include entities suchcentral units or distributed units.

The RAN may include a central unit (CU) and distributed units (DUs). A5G BS (e.g., gNB, 5G Node B, Node B, transmit receive point (TRP),access point (AP)) may correspond to one or multiple BSs. 5G cells canbe configured as access cells (ACells) or data only cells (DCells). Forexample, the RAN (e.g., a central unit or distributed unit) canconfigure the cells. DCells may be cells used for carrier aggregation ordual connectivity, but not used for initial access, cellselection/reselection, or handover. In some cases, DCells may nottransmit synchronization signals—in some case cases DCells may transmitSS. 5G BSs may transmit downlink signals to UEs indicating the celltype. Based at least in part on the cell type indication, the UE maycommunicate with the 5G BS. For example, the UE may determine 5G BSs toconsider for cell selection, access, handover, and/or measurement basedat least in part on the indicated cell type.

As indicated above, FIG. 4 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 4.

FIG. 5 illustrates an example logical architecture of a distributed RAN500, according to aspects of the present disclosure. A 5G access node506 may include an access node controller (ANC) 502. The ANC may be acentral unit (CU) of the distributed RAN 500. The backhaul interface tothe next generation core network (NG-CN) 504 may terminate at the ANC.The backhaul interface to neighboring next generation access nodes(NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs508 (which may also be referred to as BSs, 5G BSs, Node Bs, 5G NBs, APs,gNB, or some other term). As described above, a TRP may be usedinterchangeably with “cell.”

The TRPs 508 may be a distributed unit (DU). The TRPs may be connectedto one ANC (ANC 502) or more than one ANC (not illustrated). Forexample, for RAN sharing, radio as a service (RaaS), and servicespecific AND deployments, the TRP may be connected to more than one ANC.A TRP may include one or more antenna ports. The TRPs may be configuredto individually (e.g., dynamic selection) or jointly (e.g., jointtransmission) serve traffic to a UE. In some aspects, a TRP 508 may usewaveform signaling for downlink communications to notify a UE of a typeof waveform being used for a downlink communication, thereby conservingUE resources that would otherwise be wasted attempting to process thedownlink communication using multiple types of waveforms.

The local architecture of RAN 500 may be used to illustrate fronthauldefinition. The architecture may be defined that support fronthaulingsolutions across different deployment types. For example, thearchitecture may be based at least in part on transmit networkcapabilities (e.g., bandwidth, latency, and/or jitter).

The architecture may share features and/or components with LTE.According to aspects, the next generation AN (NG-AN) 510 may supportdual connectivity with 5G. The NG-AN may share a common fronthaul forLTE and 5G.

The architecture may enable cooperation between and among TRPs 508. Forexample, cooperation may be preset within a TRP and/or across TRPs viathe ANC 502. According to aspects, no inter-TRP interface may beneeded/present.

According to aspects, a dynamic configuration of split logical functionsmay be present within the architecture of RAN 500. The PDCP, RLC, MACprotocol may be adaptably placed at the ANC or TRP.

According to certain aspects, a BS may include a central unit (CU)(e.g., ANC 502) and/or one or more distributed units (e.g., one or moreTRPs 508).

As indicated above, FIG. 5 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 5.

FIG. 6 illustrates an example physical architecture of a distributed RAN600, according to aspects of the present disclosure. A centralized corenetwork unit (C-CU) 602 may host core network functions. The C-CU may becentrally deployed. C-CU functionality may be offloaded (e.g., toadvanced wireless services (AWS)), in an effort to handle peak capacity.

A centralized RAN unit (C-RU) 604 may host one or more ANC functions.Optionally, the C-RU may host core network functions locally. The C-RUmay have distributed deployment. The C-RU may be closer to the networkedge.

A distributed unit (DU) 606 may host one or more TRPs. The DU may belocated at edges of the network with radio frequency (RF) functionality.

As indicated above, FIG. 6 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 6.

FIG. 7 is a diagram 700 showing an example of a DL-centric subframe orwireless communication structure. The DL-centric subframe may include acontrol portion 702. The control portion 702 may exist in the initial orbeginning portion of the DL-centric subframe. The control portion 702may include various scheduling information and/or control informationcorresponding to various portions of the DL-centric subframe. In someconfigurations, the control portion 702 may be a physical DL controlchannel (PDCCH), as indicated in FIG. 7.

The DL-centric subframe may also include a DL data portion 704. The DLdata portion 704 may sometimes be referred to as the payload of theDL-centric subframe. The DL data portion 704 may include thecommunication resources utilized to communicate DL data from thescheduling entity (e.g., UE or BS) to the subordinate entity (e.g., UE).In some configurations, the DL data portion 704 may be a physical DLshared channel (PDSCH). In some aspects, a waveform indication for thePDSCH may be carried in the PDCCH, as described in more detail elsewhereherein.

The DL-centric subframe may also include an UL short burst portion 706.The UL short burst portion 706 may sometimes be referred to as an ULburst, an UL burst portion, a common UL burst, a short burst, an ULshort burst, a common UL short burst, a common UL short burst portion,and/or various other suitable terms. In some aspects, the UL short burstportion 706 may include one or more reference signals. Additionally, oralternatively, the UL short burst portion 706 may include feedbackinformation corresponding to various other portions of the DL-centricsubframe. For example, the UL short burst portion 706 may includefeedback information corresponding to the control portion 702 and/or theDL data portion 704. Non-limiting examples of information that may beincluded in the UL short burst portion 706 include an ACK signal (e.g.,a PUCCH ACK, a PUSCH ACK, an immediate ACK), a NACK signal (e.g., aPUCCH NACK, a PUSCH NACK, an immediate NACK), a scheduling request (SR),a buffer status report (BSR), a HARQ indicator, a channel stateindication (CSI), a channel quality indicator (CQI), a soundingreference signal (SRS), a demodulation reference signal (DMRS), PUSCHdata, and/or various other suitable types of information. The UL shortburst portion 706 may include additional or alternative information,such as information pertaining to random access channel (RACH)procedures, scheduling requests, and various other suitable types ofinformation.

As illustrated in FIG. 7, the end of the DL data portion 704 may beseparated in time from the beginning of the UL short burst portion 706.This time separation may sometimes be referred to as a gap, a guardperiod, a guard interval, and/or various other suitable terms. Thisseparation provides time for the switch-over from DL communication(e.g., reception operation by the subordinate entity (e.g., UE)) to ULcommunication (e.g., transmission by the subordinate entity (e.g., UE)).The foregoing is merely one example of a DL-centric wirelesscommunication structure, and alternative structures having similarfeatures may exist without necessarily deviating from the aspectsdescribed herein.

As indicated above, FIG. 7 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 7.

FIG. 8 is a diagram 800 showing an example of an UL-centric subframe orwireless communication structure. The UL-centric subframe may include acontrol portion 802. The control portion 802 may exist in the initial orbeginning portion of the UL-centric subframe. The control portion 802 inFIG. 8 may be similar to the control portion 702 described above withreference to FIG. 7. In some configurations, the control portion 802 maybe a physical DL control channel (PDCCH). In some aspects, the PDCCH maycarry a waveform indication for another downlink channel, as describedin more detail elsewhere herein.

The UL-centric subframe may also include an UL long burst portion 804.The UL long burst portion 804 may sometimes be referred to as thepayload of the UL-centric subframe. The UL portion may refer to thecommunication resources utilized to communicate UL data from thesubordinate entity (e.g., UE) to the scheduling entity (e.g., UE or BS).

As illustrated in FIG. 8, the end of the control portion 802 may beseparated in time from the beginning of the UL long burst portion 804.This time separation may sometimes be referred to as a gap, guardperiod, guard interval, and/or various other suitable terms. Thisseparation provides time for the switch-over from DL communication(e.g., reception operation by the scheduling entity) to UL communication(e.g., transmission by the scheduling entity).

The UL-centric subframe may also include an UL short burst portion 806.The UL short burst portion 806 in FIG. 8 may be similar to the UL shortburst portion 706 described above with reference to FIG. 7, and mayinclude any of the information described above in connection with FIG.7. The foregoing is merely one example of an UL-centric wirelesscommunication structure and alternative structures having similarfeatures may exist without necessarily deviating from the aspectsdescribed herein.

In some circumstances, two or more subordinate entities (e.g., UEs) maycommunicate with each other using sidelink signals. Real-worldapplications of such sidelink communications may include public safety,proximity services, UE-to-network relaying, vehicle-to-vehicle (V2V)communications, Internet of Everything (IoE) communications, IoTcommunications, mission-critical mesh, and/or various other suitableapplications. Generally, a sidelink signal may refer to a signalcommunicated from one subordinate entity (e.g., UE1) to anothersubordinate entity (e.g., UE2) without relaying that communicationthrough the scheduling entity (e.g., UE or BS), even though thescheduling entity may be utilized for scheduling and/or controlpurposes. In some examples, the sidelink signals may be communicatedusing a licensed spectrum (unlike wireless local area networks, whichtypically use an unlicensed spectrum).

In one example, a wireless communication structure, such as a frame, mayinclude both UL-centric subframes and DL-centric subframes. In thisexample, the ratio of UL-centric subframes to DL-centric subframes in aframe may be dynamically adjusted based at least in part on the amountof UL data and the amount of DL data that are transmitted. For example,if there is more UL data, then the ratio of UL-centric subframes toDL-centric subframes may be increased. Conversely, if there is more DLdata, then the ratio of UL-centric subframes to DL-centric subframes maybe decreased.

As indicated above, FIG. 8 is provided merely as an example. Otherexamples are possible and may differ from what was described with regardto FIG. 8.

In 5G, different types of waveforms may be used for uplink and/ordownlink communications. For example, such communications may betransmitted and/or received using a DFT-s-OFDM waveform, a CP-OFDMwaveform, and/or the like, depending on one or more factors, such as anetwork condition, a performance parameter, a type of communicationbeing transmitted, and/or the like. For example, a DFT-s-OFDM waveformmay be used to achieve performance benefits associated with a lower peakto average power ratio (PAPR), a CP-OFDM waveform may be used to achieveperformance benefits associated with a higher spectral efficiency,and/or the like.

When a base station is capable of using multiple different types ofwaveforms for a downlink communication to a UE, the UE may wasteprocessing resources attempting to receive and/or process the downlinkcommunication. For example, the UE may cycle through various possibletypes of waveforms in an attempt to process the downlink communication.Techniques described herein use waveform signaling for downlinkcommunications to notify the UE of a type of waveform being used for adownlink communication, thereby conserving UE resources (e.g.,processing resources, memory resources, RF resources, and/or the like)that would otherwise be wasted attempting to process the downlinkcommunication using multiple types of waveforms.

FIG. 9 is a diagram illustrating an example 900 of waveform signalingfor downlink communications. As shown in FIG. 9, a UE 905 maycommunicate with a base station 910 to receive downlink communications.In some aspects, the UE 905 may correspond to the UE 120 of FIG. 1and/or one or more other UEs described herein. In some aspects, the basestation 910 may correspond to the base station 110 of FIG. 1 and/or oneor more other base stations described herein.

As shown by reference number 915, the UE 905 may receive informationfrom the base station 910 in a first downlink channel. The firstdownlink channel may use a first waveform of a plurality of waveforms.The plurality of waveforms may include, for example, a DFT-s-OFDMwaveform, a CP-OFDM waveform, a default waveform (e.g., a fixed waveformused for a particular type of signal and/or channel), and/or the like.In some aspects, the first downlink channel may be a control channel(e.g., a first control channel), a broadcast channel, and/or the like.For example, the first downlink channel may be a channel that carries aprimary synchronization signal (PSS), a channel that carries a secondarysynchronization signal (SSS), a physical broadcast channel (PBCH), aphysical downlink control channel (PDCCH), a portion of the PDCCH (e.g.,a first stage of a multi-stage PDCCH), and/or the like.

As shown by reference number 920, the first downlink channel may carry awaveform indication. The waveform indication may indicate a secondwaveform, of the plurality of waveforms, used for a second downlinkchannel. The second downlink channel may be a control channel (e.g., asecond control channel), a data channel, a unicast channel, a multicastchannel, and/or the like. For example, the second downlink channel maybe a PBCH, a PDCCH, a portion of the PDCCH (e.g., a second stage of amulti-stage PDCCH), a physical downlink shared channel (PDSCH), and/orthe like.

In some aspects, the UE 905 may acquire and/or receive information inthe first downlink channel before acquiring and/or receiving informationin the second downlink channel. For example, the first downlink channelmay be a channel that carries the PSS and/or the SSS, and the seconddownlink channel may be the PBCH, the PDCCH, a portion of the PDCCH, thePDSCH, and/or the like. Additionally, or alternatively, the firstdownlink channel may be the PBCH, and the second downlink channel may bethe PDCCH, a portion of the PDCCH, the PDSCH, and/or the like.Additionally, or alternatively, the first downlink channel may be thePDCCH, and the second downlink channel may be the PDSCH and/or the like.Additionally, or alternatively, the first downlink channel may be afirst portion of the PDCCH, and the second downlink channel may be thePDSCH, a second portion of the PDCCH, and/or the like. In some aspects,the UE 905 may receive information in the first downlink channel and thesecond downlink channel in the same transmission time interval (e.g.,slot, subframe, and/or the like). For example, the first downlinkchannel may be the control portion 702 of the DL-centric subframe shownin FIG. 7 (e.g., the PDCCH), and the second downlink channel may be theDL data portion 704 of the same DL-centric subframe (e.g., the PDSCH).

The waveform indication may indicate a second waveform to be used forone or more downlink communications in the second downlink channel. Insome aspects, the waveform indication includes a waveform identifierthat explicitly identifies the second waveform (e.g., using a first setof bits to identify a first type of waveform, a second set of bits toidentify a second type of waveform, etc.).

Additionally, or alternatively, the waveform indication may implicitlyidentify the second waveform. For example, a type of waveform may beassociated with one or more configuration parameters, such as a symbolduration, a slot (or subframe, mini-slot, etc.) structure, a bandwidth,a frequency band, a modulation or coding scheme (MCS), and/or the like.In this case, the waveform indication may indicate a symbol duration forthe one or more downlink communications, a slot (or subframe, mini-slot,etc.) structure for the one or more downlink communications, a bandwidthfor the one or more downlink communications, an MCS for the one or moredownlink communications, and/or the like. The UE 905 may use one or moreof these configuration parameters, received as the waveform indication,to determine the second waveform to be used for one or more downlinkcommunications in the second downlink channel. For example, the UE 905may compare a configuration parameter to a condition and/or a threshold,and may determine the second waveform based at least in part on whetherthe configuration parameter satisfies the condition and/or thethreshold.

Additionally, or alternatively, the type of waveform may be associatedwith a type of transmission, such as a broadcast transmission, a unicasttransmission, a multicast transmission, a control channel transmission,a data channel transmission, a transmission between base stations, atransmission between a UE and a base station, and/or the like. In thiscase, the UE 905 may use the type of transmission, received as thewaveform indication, to determine the second waveform.

In some aspects, the UE 905 may use the type of waveform identified inthe waveform indication to determine one or more configurationparameters corresponding to the identified type of waveform. Forexample, the waveform indication may include a waveform identifier, andthe UE 905 may use the waveform identifier to determine a symbolduration for the one or more downlink communications, a slot (orsubframe, mini-slot, etc.) structure for the one or more downlinkcommunications, a bandwidth for the one or more downlink communications,a frequency band for the one or more downlink communications, an MCS forthe one or more downlink communications, and/or the like. Additionally,or alternatively, the waveform indication may identify one or more firstconfiguration parameters that indicate a type of waveform, and the UE905 may use one or more first configuration parameters and/or the typeof waveform to determine one or more second configuration parametersassociated with the type of waveform. In some aspects, the waveformindication may narrow the possible choices of configuration parameters(e.g., to one or more configuration parameters that can be used with awaveform), and the configuration parameter to be used may be signaledfrom the base station 910 to the UE 905 using less overhead (e.g., fewerbits) than if there were more possible choices for the configurationparameters.

As shown by reference number 925, the UE 905 may receive one or moredownlink communications in the second downlink channel using the secondwaveform. In some aspects, the first waveform and the second waveformare different (e.g., are different types of waveforms). For example, thefirst waveform may be a default waveform, and the second waveform may bea DFT-s-OFDM waveform, a CP-OFDM waveform, and/or the like. In someaspects, the UE 905 may determine the default waveform based at least inpart on a frequency band associated with the UE 905 (e.g., a frequencyband in which the one or more downlink communications are to bereceived), a system bandwidth (e.g., signaled in a master informationblock, a system information block, etc.), and/or the like. In someaspects, the first waveform may be a DFT-s-OFDM waveform, and the secondwaveform may be a CP-OFDM waveform. In some aspects, the first waveformmay be a CP-OFDM waveform, and the second waveform may be a DFT-s-OFDMwaveform. In some aspects, the first waveform and the second waveformare the same (e.g., a same type of waveform). In this case, the waveformindication may include a value (e.g., a bit) that indicates that thesecond waveform is a same type of waveform as the first waveform.

In some aspects, the UE 905 may receive a reference signal or a datatone using pre-DFT spread multiplexing or time division multiplexing(TDM) when the second waveform is the DFT-s-OFDM waveform. Similarly,the UE 905 may receive a reference signal or a data tone using FDM orTDM when the second waveform is the OFDM waveform. In this way, the UE905 may properly process signals received using a particular type ofwaveform by using a reference signal and/or a data tone corresponding tothe particular type of waveform.

As shown by reference number 930, the UE 905 may determine the secondwaveform based at least in part on the waveform indication received inthe first downlink channel, and may process one or more downlinkcommunications received in the second downlink channel using the secondwaveform. For example, the UE 905 may process downlink communicationsdifferently depending on a type of waveform used to transmit thedownlink communications. Thus, by receiving an indication of thewaveform used for the downlink communications, the UE 905 may correctlyprocess the downlink communications without attempting to process thedownlink communications using multiple types of waveforms, therebyconserving resources of the UE (e.g., processing resources, memoryresources, radio resources, and/or the like). Furthermore, the basestation 910 may dynamically select a waveform to be used for downlinkcommunications depending on network conditions, traffic requirements,and/or the like, thereby improving usage of network resources.

In some aspects, the UE 905 may process the one or more downlinkcommunications using interference cancellation based at least in part onan indication of a waveform, of the plurality of waveforms, associatedwith downlink communications of another UE, as described below inconnection with FIG. 10.

As indicated above, FIG. 9 is provided as an example. Other examples arepossible and may differ from what was described with respect to FIG. 9.

FIG. 10 is a diagram illustrating an example 1000 of waveform signalingfor downlink communications. As shown in FIG. 10, a base station 1005may transmit respective downlink communications to a first UE 1010 and asecond UE 1015, and the first UE 1010 and the second UE 1015 may receivethe respective downlink communications from the base station 1005. Insome aspects, the base station 1005 may correspond to the base station110 of FIG. 1, the base station 910 of FIG. 9, and/or one or more otherbase stations described herein. In some aspects, the first UE 1010 maycorrespond to the UE 120 of FIG. 1, the UE 905 of FIG. 9, and/or one ormore other UEs described herein. In some aspects, the second UE 1015 maycorrespond to the UE 120 of FIG. 1, the UE 905 of FIG. 9, and/or one ormore other UEs described herein.

As shown by reference number 1020, the base station 1005 may generate afirst transmission layer of a multi-layer communication using a firstwaveform, of a plurality of waveforms, and may generate a secondtransmission layer of the multi-layer communication using a secondwaveform of the plurality of waveforms. In some aspects, the pluralityof waveforms include a DFT-s-OFDM waveform, a CP-OFDM waveform, and/orthe like. In some aspects, the first waveform and the second waveformmay be different. For example, the base station 1005 may generate thefirst transmission layer using a DFT-s-OFDM waveform, and may generatethe second transmission layer using a CP-OFDM waveform, or vice versa.

The multi-layer communication may include multiple transmissions thatare transmitted using a same time resource (e.g., simultaneously orconcurrently) and a same frequency resource. For example, themulti-layer communication may include a MIMO communication, such as amulti-user MIMO (MU-MIMO) communication, a multi-user superpositiontransmission (MUST), a downlink version of a non-orthogonal multipleaccess (NOMA) communication, and/or the like.

As shown by reference numbers 1025 and 1030, the base station 1005 maytransmit the first transmission on a first layer (e.g., a first layer ofinformation, a first transmission layer, etc.) to the first UE 1010using the first waveform, and may transmit the second transmission(e.g., a second layer of information, a second transmission layer, etc.)on the second layer to the second UE 1015 using the second waveform. Insome aspects, the base station 1005 may transmit the first transmissionon the first layer and the second transmission on the second layer usingdifferent antenna beams (e.g., using beamforming, precoding, and/or thelike).

As shown by reference number 1035, the base station 1005 may transmitthe first transmission on the first layer and the second transmission onthe second layer using a same time resource and a same frequencyresource (e.g., using MU-MIMO). For example, the base station 1005 maytransmit the first transmission and the second transmissionsimultaneously using two transmission layers over the same frequency.

As shown by reference number 1040, the first UE 1010 may receive a firstindication of the first waveform used for the first transmission layer,and may use the first indication to process the first transmission layer(e.g., to process one or more first downlink communications included inthe first transmission layer). For example, the base station 1005 maytransmit the first indication (e.g., a waveform indication) to the firstUE 1010, and the first indication may indicate the first waveform usedfor the first transmission layer. The first indication may indicate thefirst waveform according to any of the techniques described above inconnection with FIG. 9. For example, the first indication may include awaveform identifier that identifies the first waveform, may identify oneor more configuration parameters that correspond to the first waveform,and/or the like. Additionally, or alternatively, the first indicationmay include a layer identifier associated with a MU-MIMO communication,and the layer identifier may correspond to a waveform. In this case, thefirst UE 1010 may use the layer identifier to determine the firstwaveform. In some aspects, the first UE 1010 may receive the firstindication in a similar manner as the waveform indication, as isdescribed above in connection with FIG. 9.

Additionally, or alternatively, the first UE 1010 may receive a secondindication of the second waveform used for the second transmissionlayer, and may use the second indication to process the firsttransmission layer. For example, the base station 1005 may transmit thesecond indication (e.g., a waveform indication) to the first UE 1010,and the second indication may indicate the second waveform used for thesecond transmission layer. The first UE 1010 may use the secondindication of the second waveform to perform interference cancellation.In this way, the first UE 1010 may improve processing of the firsttransmission layer to correctly receive the first transmission layer,thereby conserving network resources by reducing retransmissions.

As shown by reference number 1045, the second UE 1015 may receive asecond indication of the second waveform used for the secondtransmission layer, and may use the second indication to process thesecond transmission layer (e.g., to process one or more second downlinkcommunications included in the second transmission layer). For example,the base station 1005 may transmit the second indication (e.g., awaveform indication) to the second UE 1015, and the second indicationmay indicate the second waveform used for the second transmission layer.The second indication may indicate the second waveform according to anyof the techniques described above in connection with FIG. 9. Forexample, the second indication may include a waveform identifier thatidentifies the second waveform, may identify one or more configurationparameters that correspond to the second waveform, and/or the like.Additionally, or alternatively, the second indication may include alayer identifier associated with a MU-MIMO communication, and the layeridentifier may correspond to a waveform. In this case, the second UE1015 may use the layer identifier to determine the second waveform. Insome aspects, the second UE 1015 may receive the second indication in asimilar manner as the waveform indication, as is described above inconnection with FIG. 9.

Additionally, or alternatively, the second UE 1015 may receive a firstindication of the first waveform used for the first transmission layer,and may use the first indication to process the second transmissionlayer. For example, the base station 1005 may transmit the firstindication (e.g., a waveform indication) to the second UE 1015, and thefirst indication may indicate the first waveform used for the firsttransmission layer. The second UE 1015 may use the first indication ofthe first waveform to perform interference cancellation. In this way,the second UE 1015 may improve processing of the second transmissionlayer to correctly receive the second transmission layer, therebyconserving network resources by reducing retransmissions.

As indicated above, FIG. 10 is provided as an example. Other examplesare possible and may differ from what was described with respect to FIG.10.

FIG. 11 is a flow chart of a method 1100 of wireless communication. Themethod may be performed by a UE (e.g., the UE 120 of FIG. 1, the UE 905of FIG. 9, the first UE 1010 of FIG. 10, the second UE 1015 of FIG. 10,the apparatus 1402 and/or 1402′ of FIGS. 14 and/or 15, and/or the like).

At 1110, the UE may receive a waveform indication in a first downlinkchannel that uses a first waveform. For example, the UE may receive awaveform indication in a first downlink channel that uses a firstwaveform of a plurality of waveforms, as described above in connectionwith FIG. 9. In some aspects, the first downlink channel is at least oneof: a first control channel, or a broadcast channel. In some aspects,the first waveform is a default waveform used for the first downlinkchannel. In some aspects, the default waveform is determined based atleast in part on: a frequency band associated with the one or moredownlink communications, a system bandwidth, or some combinationthereof.

In some aspects, the plurality of waveforms include a DFT-s-OFDMwaveform and a CP-OFDM waveform. In some aspects, at least one of areference signal or a data tone is received using pre-DFT spreadmultiplexing or time division multiplexing when the second waveform isthe DFT-s-OFDM waveform, or at least one of a reference signal or a datatone is received using FDM or time division multiplexing when the secondwaveform is the CP-OFDM waveform.

At 1120, the UE may determine a second waveform to be used for one ormore downlink communications in a second downlink channel. For example,the UE may determine a second waveform, of the plurality of waveforms,to be used for one or more downlink communications in a second downlinkchannel based at least in part on the waveform indication received inthe first downlink channel, as described above in connection with FIG.9. In some aspects, the second downlink channel is at least one of: asecond control channel, a data channel, a unicast channel, or amulticast channel. In some aspects, the first waveform and the secondwaveform are different. In some aspects, the first waveform and thesecond waveform are the same.

In some aspects, the waveform indication indicates a waveform identifierthat explicitly identifies the second waveform. In some aspects, thewaveform indication includes one or more configuration parameters thatimplicitly identify the second waveform. In some aspects, the one ormore configuration parameters include one or more of: a symbol durationfor the one or more downlink communications, a slot structure for theone or more downlink communications, a bandwidth for the one or moredownlink communications, a frequency band for the one or more downlinkcommunications, a modulation or coding scheme for the one or moredownlink communications, or some combination thereof. For example, insome aspects, pi/2 BPSK modulation may always be associated with the useof DFT-s-OFDM.

In some aspects, the UE may determine, based at least in part on thewaveform indication, one or more configuration parameters associatedwith the one or more downlink communications. In some aspects, the oneor more configuration parameters include one or more of: a symbolduration for the one or more downlink communications, a slot structurefor the one or more downlink communications, a bandwidth for the one ormore downlink communications, a frequency band for the one or moredownlink communications a modulation or coding scheme for the one ormore downlink communications, or some combination thereof.

At 1130, the UE may process the one or more downlink communicationsreceived in the second downlink channel using the second waveform. Forexample, the UE may receive the one or more downlink communications inthe second downlink channel, and may process the one or more downlinkcommunications using the second waveform, as described above inconnection with FIG. 9. In some aspects, the waveform indication and theone or more downlink communications are received in a same transmissiontime interval. In some aspects, the UE may process the one or moredownlink communications using interference cancellation based at leastin part on an indication of a waveform, of the plurality of waveforms,associated with downlink communications of another UE, as describedabove in connection with FIG. 10.

Although FIG. 11 shows example blocks of a method of wirelesscommunication, in some aspects, the method may include additionalblocks, fewer blocks, different blocks, or differently arranged blocksthan those shown in FIG. 11. Additionally, or alternatively, two or moreblocks shown in FIG. 11 may be performed in parallel.

FIG. 12 is a flow chart of a method 1200 of wireless communication. Themethod may be performed by a base station (e.g., the base station 110 ofFIG. 1, the base station 910 of FIG. 9, the base station 1005 of FIG.10, the apparatus 1602 and/or 1602′ of FIGS. 16 and/or 17, and/or thelike).

At 1210, the base station may generate a first transmission layer of amulti-layer communication using a first waveform. For example, the basestation may generate a first transmission layer of a multi-layercommunication using a first waveform of a plurality of waveforms, asdescribed above in connection with FIG. 10. In some aspects, themulti-layer communication is a MU-MIMO communication. In some aspects,the plurality of waveforms include a DFT-s-OFDM waveform and a CP-OFDMwaveform. In some aspects, generating the first transmission layer mayinclude generating, encoding, modulating, mapping, etc. firstinformation to be included in the first transmission layer.

At 1220, the base station may generate a second transmission layer ofthe multi-layer communication using a second waveform. For example, thebase station may generate a second transmission layer of the multi-layercommunication using a second waveform of the plurality of waveforms, asdescribed above in connection with FIG. 10. In some aspects, the firstwaveform and the second waveform are different. In some aspects,generating the second transmission layer may include generating,encoding, modulating, mapping, etc. second information to be included inthe second transmission layer.

At 1230, the base station may transmit the first transmission layer andthe second transmission layer using a same time resource and a samefrequency resource. For example, the base station may transmit the firsttransmission layer and the second transmission layer using a same timeresource and a same frequency resource, wherein the first transmissionlayer is transmitted using the first waveform and the secondtransmission layer is transmitted using the second waveform, asdescribed above in connection with FIG. 10. In some aspects, the firsttransmission layer is transmitted to a first UE and the secondtransmission layer is transmitted to a second UE. In some aspects, thefirst transmission layer and the second transmission layer aretransmitted using different antenna beams of the base station. In someaspects, the base station may transmit at least one of: an indication ofthe first waveform to the second UE, or an indication of the secondwaveform to the first UE.

Although FIG. 12 shows example blocks of a method of wirelesscommunication, in some aspects, the method may include additionalblocks, fewer blocks, different blocks, or differently arranged blocksthan those shown in FIG. 12. Additionally, or alternatively, two or moreblocks shown in FIG. 12 may be performed in parallel.

FIG. 13 is a flow chart of a method 1300 of wireless communication. Themethod may be performed by a UE (e.g., the UE 120 of FIG. 1, the UE 905of FIG. 9, the first UE 1010 of FIG. 10, the second UE 1015 of FIG. 10,the apparatus 1402 and/or 1402′ of FIGS. 14 and/or 15, and/or the like).

At 1310, the UE may receive a first indication of a first waveform to beused for one or more downlink communications associated with a first UE.For example, a first UE may receive a first indication of a firstwaveform, of a plurality of waveforms, to be used for one or moredownlink communications associated with the first UE, as described abovein connection with FIG. 10. In some aspects, the multi-layercommunication is a MU-MIMO communication. In some aspects, the firstindication may include a layer identifier associated with the MU-MIMOcommunication. In some aspects, the plurality of waveforms include aDFT-s-OFDM waveform and a CP-OFDM waveform.

At 1320, the UE may receive a second indication of a second waveformassociated with downlink communications of a second UE. For example, thefirst UE may receive a second indication of a second waveform, of theplurality of waveforms, associated with downlink communications of asecond UE, as described above in connection with FIG. 10. In someaspects, the second indication may include a layer identifier associatedwith the MU-MIMO communication.

At 1330, the UE may receive the one or more downlink communicationsusing the first waveform. For example, the first UE may receive the oneor more downlink communications using the first waveform, as describedabove in connection with FIG. 10. For example, a base station maygenerate the one or more downlink communications using the firstwaveform, and may transmit the one or more downlink communications tothe first UE.

At 1340, the UE may process the one or more downlink communicationsbased at least in part on the second indication. For example, the firstUE may process the one or more downlink communications based at least inpart on the second indication of the second waveform, as described abovein connection with FIG. 10. In some aspects, the first UE may processthe one or more downlink communications using interference cancellationbased at least in part on the second indication of the second waveformassociated with the downlink communications of the second UE.

Although FIG. 13 shows example blocks of a method of wirelesscommunication, in some aspects, the method may include additionalblocks, fewer blocks, different blocks, or differently arranged blocksthan those shown in FIG. 13. Additionally, or alternatively, two or moreblocks shown in FIG. 13 may be performed in parallel.

FIG. 14 is a conceptual data flow diagram 1400 illustrating the dataflow between different modules/means/components in an example apparatus1402. The apparatus 1402 may be a UE. In some aspects, the apparatus1402 includes a reception module 1404, a determination module 1406, aprocessing module 1408, a transmission module 1410, and/or the like.

In some aspects, the reception module 1404 may receive a waveformindication, as data 1412 from a base station 1450, in a first downlinkchannel that uses a first waveform. The reception module 1404 mayprovide the waveform indication to the determination module 1406 as data1414. The determination module 1406 may use the waveform indication todetermine a second waveform to be used for one or more downlinkcommunications in a second downlink channel. The determination module1406 may provide an indication of the second waveform to the receptionmodule 1404 as data 1416. The reception module 1404 may use thisindication to receive the one or more downlink communications (e.g., asadditional data 1412) in the second downlink channel using the secondwaveform. Additionally, or alternatively, the determination module 1406may provide an indication of the second waveform to the processingmodule 1408 as data 1418. The processing module 1408 may process the oneor more downlink communications, which may be received from thereception module 1404 as data 1420, using the indication of the secondwaveform. In some aspects, the processing module 1408 may provide data1422 to the transmission module 1410, and the transmission module 1410may transmit data 1424 (e.g., a response to the one or more downlinkcommunications) to the base station 1450.

In some aspects, the reception module 1404 may receive a firstindication of a first waveform and a second indication of a secondwaveform as data 1412 from the base station 1450. Furthermore, thereception module 1404 may receive one or more downlink communications,as additional data 1412, using the first waveform. The reception module1404 may provide the first indication, the second indication, and theone or more downlink communications to the processing module 1408 asdata 1420. The processing module 1408 may process the one or moredownlink communications using the first indication and/or the secondindication. In some aspects, the processing module 1408 and/or anothermodule of the apparatus 1402 may generate data 1422 based at least inpart on processing the one or more downlink communications, and mayprovide data 1422 to the transmission module 1410 for transmission tothe base station 1450 as data 1424.

The apparatus may include additional modules that perform each of theblocks of the algorithm in the aforementioned flow charts of FIGS. 11and/or 13. As such, each block in the aforementioned flow charts ofFIGS. 11, and/or 13 may be performed by a module and the apparatus mayinclude one or more of those modules. The modules may be one or morehardware components specifically configured to carry out the statedprocesses/algorithm, implemented by a processor configured to performthe stated processes/algorithm, stored within a computer-readable mediumfor implementation by a processor, or some combination thereof.

The number and arrangement of modules shown in FIG. 14 are provided asan example. In practice, there may be additional modules, fewer modules,different modules, or differently arranged modules than those shown inFIG. 14. Furthermore, two or more modules shown in FIG. 14 may beimplemented within a single module, or a single module shown in FIG. 14may be implemented as multiple, distributed modules. Additionally, oralternatively, a set of modules (e.g., one or more modules) shown inFIG. 14 may perform one or more functions described as being performedby another set of modules shown in FIG. 14.

FIG. 15 is a diagram 1500 illustrating an example of a hardwareimplementation for an apparatus 1402′ employing a processing system1502. The apparatus 1402′ may be a UE.

The processing system 1502 may be implemented with a bus architecture,represented generally by the bus 1504. The bus 1504 may include anynumber of interconnecting buses and bridges depending on the specificapplication of the processing system 1502 and the overall designconstraints. The bus 1504 links together various circuits including oneor more processors and/or hardware modules, represented by the processor1506, the modules 1404, 1406, 1408, and/or 1410, and thecomputer-readable medium/memory 1508. The bus 1504 may also link variousother circuits such as timing sources, peripherals, voltage regulators,and power management circuits, which are well known in the art, andtherefore, will not be described any further.

The processing system 1502 may be coupled to a transceiver 1510. Thetransceiver 1510 is coupled to one or more antennas 1512. Thetransceiver 1510 provides a means for communicating with various otherapparatus over a transmission medium. The transceiver 1510 receives asignal from the one or more antennas 1512, extracts information from thereceived signal, and provides the extracted information to theprocessing system 1502, specifically the reception module 1404. Inaddition, the transceiver 1510 receives information from the processingsystem 1502, specifically the transmission module 1410, and based atleast in part on the received information, generates a signal to beapplied to the one or more antennas 1512. The processing system 1502includes a processor 1506 coupled to a computer-readable medium/memory1508. The processor 1506 is responsible for general processing,including the execution of software stored on the computer-readablemedium/memory 1508. The software, when executed by the processor 1506,causes the processing system 1502 to perform the various functionsdescribed supra for any particular apparatus. The computer-readablemedium/memory 1508 may also be used for storing data that is manipulatedby the processor 1506 when executing software. The processing systemfurther includes at least one of the modules 1404, 1406, 1408, and/or1410. The modules may be software modules running in the processor 1506,resident/stored in the computer readable medium/memory 1508, one or morehardware modules coupled to the processor 1506, or some combinationthereof. The processing system 1502 may be a component of the UE 120 andmay include the memory 282 and/or at least one of the TX MIMO processor266, the RX processor 258, and/or the controller/processor 280.

In some aspects, the apparatus 1402/1402′ for wireless communication mayinclude means for receiving a waveform indication in a first downlinkchannel that uses a first waveform, means for determining a secondwaveform to be used for one or more downlink communications in a seconddownlink channel based at least in part on the waveform indicationreceived in the first downlink channel, means for receiving the one ormore downlink communications in the second downlink channel using thesecond waveform, means for processing the one or more downlinkcommunications received in the second downlink channel using the secondwaveform, means for determining a configuration parameter based at leastin part on the waveform indication, and/or the like. Additionally, oralternatively, the apparatus 1402/1402′ for wireless communication mayinclude means for receiving a first indication of a first waveform to beused for one or more downlink communications associated with a first UE,means for receiving a second indication of a second waveform associatedwith downlink communications of a second UE, means for receiving the oneor more downlink communications using the first waveform, means forprocessing the one or more downlink communications based at least inpart on the second indication of the second waveform, and/or the like.The aforementioned means may be one or more of the aforementionedmodules of the apparatus 1402 and/or the processing system 1502 of theapparatus 1402′ configured to perform the functions recited by theaforementioned means. As described supra, the processing system 1502 mayinclude the TX MIMO processor 266, the RX processor 258, and/or thecontroller/processor 280. As such, in one configuration, theaforementioned means may be the TX MIMO processor 266, the RX processor258, and/or the controller/processor 280 configured to perform thefunctions recited by the aforementioned means.

FIG. 15 is provided as an example. Other examples are possible and maydiffer from what was described in connection with FIG. 15.

FIG. 16 is a conceptual data flow diagram 1600 illustrating the dataflow between different modules/means/components in an example apparatus1602. The apparatus 1602 may be a base station. In some aspects, theapparatus 1602 includes a reception module 1604, a generation module1606, a transmission module 1608, and/or the like.

The reception module 1604 may receive data 1610 from a network deviceand/or a UE 1650, such as data destined for another UE. The receptionmodule 1604 may provide information, as data 1612, to the generationmodule 1606 to trigger the generation of one or more transmissions toanother UE 1650. The generation module 1606 may generate a first a firsttransmission layer of a multi-layer communication using a firstwaveform, and may generate a second transmission layer of themulti-layer communication using a second waveform. The generation module1606 may provide the first and second transmission layers to thetransmission module 1608 as data 1614. The transmission module 1608 maytransmit the first transmission layer and the second transmission layer(e.g., as data 1616 to multiple UEs 1650) using a same time resource anda same frequency resource.

The apparatus may include additional modules that perform each of theblocks of the algorithm in the aforementioned flow chart of FIG. 12. Assuch, each block in the aforementioned flow chart of FIG. 12 may beperformed by a module and the apparatus may include one or more of thosemodules. The modules may be one or more hardware components specificallyconfigured to carry out the stated processes/algorithm, implemented by aprocessor configured to perform the stated processes/algorithm, storedwithin a computer-readable medium for implementation by a processor, orsome combination thereof.

The number and arrangement of modules shown in FIG. 16 are provided asan example. In practice, there may be additional modules, fewer modules,different modules, or differently arranged modules than those shown inFIG. 16. Furthermore, two or more modules shown in FIG. 16 may beimplemented within a single module, or a single module shown in FIG. 16may be implemented as multiple, distributed modules. Additionally, oralternatively, a set of modules (e.g., one or more modules) shown inFIG. 16 may perform one or more functions described as being performedby another set of modules shown in FIG. 16.

FIG. 17 is a diagram 1700 illustrating an example of a hardwareimplementation for an apparatus 1602′ employing a processing system1702. The apparatus 1602′ may be a base station.

The processing system 1702 may be implemented with a bus architecture,represented generally by the bus 1704. The bus 1704 may include anynumber of interconnecting buses and bridges depending on the specificapplication of the processing system 1702 and the overall designconstraints. The bus 1704 links together various circuits including oneor more processors and/or hardware modules, represented by the processor1706, the modules 1604, 1606, and/or 1608, and the computer-readablemedium/memory 1708. The bus 1704 may also link various other circuitssuch as timing sources, peripherals, voltage regulators, and powermanagement circuits, which are well known in the art, and therefore,will not be described any further.

The processing system 1702 may be coupled to a transceiver 1710. Thetransceiver 1710 is coupled to one or more antennas 1712. Thetransceiver 1710 provides a means for communicating with various otherapparatus over a transmission medium. The transceiver 1710 receives asignal from the one or more antennas 1712, extracts information from thereceived signal, and provides the extracted information to theprocessing system 1702, specifically the reception module 1604. Inaddition, the transceiver 1710 receives information from the processingsystem 1702, specifically the transmission module 1608, and based atleast in part on the received information, generates a signal to beapplied to the one or more antennas 1712. The processing system 1702includes a processor 1706 coupled to a computer-readable medium/memory1708. The processor 1706 is responsible for general processing,including the execution of software stored on the computer-readablemedium/memory 1708. The software, when executed by the processor 1706,causes the processing system 1702 to perform the various functionsdescribed supra for any particular apparatus. The computer-readablemedium/memory 1708 may also be used for storing data that is manipulatedby the processor 1706 when executing software. The processing systemfurther includes at least one of the modules 1604, 1606, and/or 1608.The modules may be software modules running in the processor 1706,resident/stored in the computer readable medium/memory 1708, one or morehardware modules coupled to the processor 1706, or some combinationthereof. The processing system 1702 may be a component of the BS 110 andmay include the memory 242 and/or at least one of the TX MIMO processor230, the RX processor 238, and/or the controller/processor 240.

In some aspects, the apparatus 1602/1602′ for wireless communicationincludes means for generating a first transmission layer of amulti-layer communication using a first waveform of a plurality ofwaveforms, means for generating a second transmission layer of themulti-layer communication using a second waveform of the plurality ofwaveforms, means for transmitting the first transmission layer and thesecond transmission layer using a same time resource and a samefrequency resource, means for transmitting at least one of an indicationof the first waveform or an indication of the second waveform, and/orthe like. The aforementioned means may be one or more of theaforementioned modules of the apparatus 1602 and/or the processingsystem 1702 of the apparatus 1602′ configured to perform the functionsrecited by the aforementioned means. As described supra, the processingsystem 1702 may include the TX MIMO processor 230, the RX processor 238,and/or the controller/processor 240. As such, in one configuration, theaforementioned means may be the TX processor 230, the RX processor 238,and/or the controller/processor 240 configured to perform the functionsrecited by the aforementioned means.

FIG. 17 is provided as an example. Other examples are possible and maydiffer from what was described in connection with FIG. 17.

It is understood that the specific order or hierarchy of blocks in theprocesses/flow charts disclosed is an illustration of exampleapproaches. Based upon design preferences, it is understood that thespecific order or hierarchy of blocks in the processes/flow charts maybe rearranged. Further, some blocks may be combined or omitted. Theaccompanying method claims present elements of the various blocks in asample order, and are not meant to be limited to the specific order orhierarchy presented.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” The word “exemplary” is used hereinto mean “serving as an example, instance, or illustration.” Any aspectdescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other aspects. Unless specifically statedotherwise, the term “some” refers to one or more. Combinations such as“at least one of A, B, or C,” “at least one of A, B, and C,” and “A, B,C, or any combination thereof” include any combination of A, B, and/orC, and may include multiples of A, multiples of B, or multiples of C.Specifically, combinations such as “at least one of A, B, or C,” “atleast one of A, B, and C,” and “A, B, C, or any combination thereof” maybe A only, B only, C only, A and B, A and C, B and C, or A and B and C,where any such combinations may contain one or more member or members ofA, B, or C. All structural and functional equivalents to the elements ofthe various aspects described throughout this disclosure that are knownor later come to be known to those of ordinary skill in the art areexpressly incorporated herein by reference and are intended to beencompassed by the claims. Moreover, nothing disclosed herein isintended to be dedicated to the public regardless of whether suchdisclosure is explicitly recited in the claims. No claim element is tobe construed as a means plus function unless the element is expresslyrecited using the phrase “means for.”

What is claimed is:
 1. A method of wireless communication, comprising:receiving, by a first user equipment (UE), a first indication of a firstwaveform, of a plurality of waveforms, to be used for one or moredownlink communications associated with the first UE; receiving, by thefirst UE, a second indication of a second waveform, of the plurality ofwaveforms, associated with downlink communications of a second UE;receiving, by the first UE, the one or more downlink communicationsusing the first waveform; and processing, by the first UE, the one ormore downlink communications based at least in part on the secondindication of the second waveform.
 2. The method of claim 1, whereinprocessing the one or more downlink communications comprises: processingthe one or more downlink communications using interference cancellationbased at least in part on the second indication of the second waveformassociated with the downlink communications of the second UE.
 3. Themethod of claim 1, wherein the first indication includes a layeridentifier associated with a multi-user multiple-input andmultiple-output communication.
 4. The method of claim 1, wherein thefirst indication includes a waveform identifier that identifies thefirst waveform.
 5. The method of claim 1, wherein the first indicationidentifies one or more configuration parameters that correspond to thefirst waveform.
 6. The method of claim 1, wherein the first indicationincludes a layer identifier that corresponds to the first waveform. 7.The method of claim 1, further comprising: determining the firstwaveform by using a layer identifier included in the first indication.8. The method of claim 1, wherein the first waveform is used for a firsttransmission layer, and wherein the second waveform is used for a secondtransmission layer.
 9. The method of claim 1, wherein the first waveformis a discrete Fourier transform spread orthogonal frequency divisionmultiplexing (DFT-s-OFDM) waveform or a cyclic prefix orthogonalfrequency division multiplexing (CP-OFDM) waveform.
 10. The method ofclaim 1, wherein the first waveform is used to transmit the one or moredownlink communications on a first layer to the first UE, and whereinthe second waveform is used to transmit the downlink communications on asecond layer to the second UE.
 11. A method of wireless communication,comprising: generating, by a base station, a first transmission layer ofa multi-layer communication using a first waveform of a plurality ofwaveforms; generating, by the base station, a second transmission layerof the multi-layer communication using a second waveform of theplurality of waveforms, wherein the first waveform and the secondwaveform are different; and transmitting, by the base station, the firsttransmission layer and the second transmission layer using a same timeresource and a same frequency resource, wherein the first transmissionlayer is transmitted using the first waveform and the secondtransmission layer is transmitted using the second waveform.
 12. Themethod of claim 11, wherein the first transmission layer is transmittedto a first user equipment (UE) and the second transmission layer istransmitted to a second UE.
 13. The method of claim 12, furthercomprising transmitting at least one of: an indication of the firstwaveform to the second UE, or an indication of the second waveform tothe first UE.
 14. The method of claim 11, wherein the first transmissionlayer and the second transmission layer are transmitted using differentantenna beams of the base station.
 15. The method of claim 11, whereinthe first waveform is a discrete Fourier transform spread orthogonalfrequency division multiplexing (DFT-s-OFDM) waveform or a cyclic prefixorthogonal frequency division multiplexing (CP-OFDM) waveform.
 16. Themethod of claim 11, further comprising: transmitting, to a UE, a firstindication of the first waveform, and transmitting, to the UE, a secondindication of the first waveform.
 17. The method of claim 11, furthercomprising: transmitting, to a UE, an indication that includes a layeridentifier that corresponds to the first waveform.
 18. The method ofclaim 11, further comprising: transmitting, to a UE, an indication thatidentifies one or more configuration parameters that correspond to thefirst waveform.
 19. A first user equipment (UE) for wirelesscommunication, comprising: memory; and one or more processors coupled tothe memory, the memory and the one or more processors configured to:receive a first indication of a first waveform, of a plurality ofwaveforms, to be used for one or more downlink communications associatedwith the first UE; receive a second indication of a second waveform, ofthe plurality of waveforms, associated with downlink communications of asecond UE; receive the one or more downlink communications using thefirst waveform; and process the one or more downlink communicationsbased at least in part on the second indication of the second waveform.20. The first UE of claim 19, wherein, when processing the one or moredownlink communications, the memory and the one or more processors areconfigured to: process the one or more downlink communications usinginterference cancellation based at least in part on the secondindication of the second waveform associated with the downlinkcommunications of the second UE.
 21. The first UE of claim 19, whereinthe first indication includes a layer identifier associated with amulti-user multiple-input and multiple-output communication.
 22. Thefirst UE of claim 19, wherein the first indication identifies one ormore configuration parameters that correspond to the first waveform. 23.The first UE of claim 19, wherein the first indication includes a layeridentifier that corresponds to the first waveform.
 24. The first UE ofclaim 19, wherein the first waveform is a discrete Fourier transformspread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform.25. The first UE of claim 19, wherein the second waveform is a cyclicprefix orthogonal frequency division multiplexing (CP-OFDM) waveform.26. The first UE of claim 19, wherein, when receiving the one or moredownlink communications, the memory and the one or more processors areconfigured to: receive, via a first layer, the one or more downlinkcommunications using the first wave form, and wherein the first layer isdifferent from a second layer via which the second UE receives thedownlink communications using the second wave form.
 27. A base stationfor wireless communication, comprising: memory; and one or moreprocessors coupled to the memory, the memory and the one or moreprocessors configured to: generate a first transmission layer of amulti-layer communication using a first waveform of a plurality ofwaveforms; generate a second transmission layer of the multi-layercommunication using a second waveform of the plurality of waveforms,wherein the first waveform and the second waveform are different; andtransmit the first transmission layer and the second transmission layerusing a same time resource and a same frequency resource, wherein thefirst transmission layer is transmitted using the first waveform and thesecond transmission layer is transmitted using the second waveform. 28.The base station of claim 27, wherein, when transmitting the firsttransmission layer and the second transmission layer, the memory and theone or more processors are configured to: transmit the firsttransmission layer to a first user equipment (UE), and transmit thesecond transmission layer is transmitted to a second UE.
 29. The basestation of claim 27, wherein the memory and the one or more processorsare configured to: transmit at least one of: an indication of the firstwaveform to the second UE, or an indication of the second waveform tothe first UE.
 30. The base station of claim 27, wherein, whentransmitting the first transmission layer and the second transmissionlayer, the memory and the one or more processors are configured to:transmit the first transmission layer and the second transmission layerusing different antenna beams of the base station.